It sounds as if you may be practicing too much as well – when your vocal muscles get strained, like any other muscle, they can get harmed, so if when you practice, you get a sore throat, leave it for a bit. When I practice I have two or three goes a day, no longer than half an hour actual singing, especially the first practice in the morning,although there are opportunities to study and analyze the music, perhaps play it on the piano.

I do not know anything about dance, but it seems to me that you could do worse than have a few lessons, or maybe a few tips from voice teachers in your musical societies. Also, it sounds as you may be working your voice too hard – find your range, and do not over do it on the extreme ends, whether singing or practicing, and do not over practice.